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1.
This paper is devoted to the study of semi-bent functions with several parameters flexible on the finite field F2n.Boolean functions defined on F2n of the form f(r)ab(x) =Trn1(axr(2m-1))+Tr41(bx(2n-1)/5) and the form g(rs)abcd(x)=Trn1(axr(2m-1))+Tr41(bx(2n-1)/5)+Trn1(cx(2m-1)1/2+1)+Trn1(dx(2m-1)s+1) where n = 2m,m = 2(mod 4),a,c ∈ F2n,and b ∈ F(16),d ∈ F2,are investigated in constructing new classes of semi-bent functions.Some characteristic sums such as Kloosterman sums and Weil sums are employed to determine whether the above functions are semi-bent or not. 相似文献
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3.
Design of a memory polynomial predistorter for wideband envelope tracking amplifiers 总被引:1,自引:0,他引:1
Efficiency and linearity of the microwave power amplifier are critical elements for mobile communication systems. A memory polynomial baseband predistorter based on an indirect learning architecture is presented for improving the linearity of an envelope tracing (ET) amplifier with application to a wireless transmitter. To deal with large peak-to-average ratio (PAR) problem, a clipping procedure for the input signal is employed. Then the system performance is verified by simulation results. For a single carrier wideband code division multiple access (WCDMA) signal of 16-quadrature amplitude modulation (16-QAM), about 2% improvement of the error vector magnitude (EVM) is achieved at an average output power of 45.5 dBm and gain of 10.6 dB, with adjacent channel leakage ratio (ACLR) of -64.55 dBc at offset frequency of 5 MHz. Moreover, a three-carrier WCDMA signal and a third-generation (3G) long term evolution (LTE) signal are used as test signals to demonstrate the performance of the proposed linearization scheme under different bandwidth signals. 相似文献
4.
In a recent article, the authors provided an effective algorithm for both computing the global infimum of f and deciding whether or not the infimum of f is attained, where f is a multivariate polynomial over the field R of real numbers. As a complement, the authors investigate the semi- algebraically connected components of minimum points of a polynomial function in this paper. For a given multivariate polynomial f over R, it is shown that the above-mentioned algorithm can find at least one point in each semi-algebraically connected component of minimum points of f whenever f has its global minimum. 相似文献
5.
Zhou Yongwu 《系统工程与电子技术(英文版)》1999,(2)
1.INTANDUCTIONThetraditionaleconomicorderquantity(EOQ)modelswereformulatedinastaticenvironmentwhereademandtobeconstantandinflexible.Inthelasttwodecades,considerableattentionshavebeengiventoEOQmodelswithtime-varyingdemand,suchasthereferences[2-7].Viewedfromthedemandpattern,thesemodelsmaybeclassifiedastwosorts.Onesortisonlyusableforincreasingdemand.Theotherisfitfordecreasingdemand.However,inarealisticproductlifecycle,thedemandisincreasingwithtimeduringtheinitialstageofthelifecycle.Afterr… 相似文献
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1.IntroductionInthisreportwewillpresentsomecomputationalresultsforthekinematicsolutionofanin-parallelmechanismplatformdesignedattheUniversityofFlorida.Thefigureoftheplatformanalysedhereisasfollows.Figure1Theconnectingpointsjoinvenicestosidesofthepairoftriangles.Thisisaspecialcaseofwhatwehaveconsideredin[l].Sincebothofthefixedandmovingplatformsaretriangles,andsomejointcenterslieonthecorrespondingsidesofthem,wecanspecifysomeparametersin[1]foranalysis.Itturnsoutthatmorecomputationalresultscanbe… 相似文献
7.
YU Guangyi 《系统科学与系统工程学报(英文版)》1995,(1)
ASystemoftheAirPollutionAssessmentforMountainArea¥YUGuangyi(CapitalNormalUniversity,MathematicsDepartment,Beijing,100037)Abst... 相似文献
8.
Yong Wang 《系统工程与电子技术(英文版)》2012,(4):502-511
Inverse synthetic aperture radar (ISAR) imaging of ship targets is very important in the national defense. For the high maneuverability of ship targets, the Doppler frequency shift of the received signal is time-varying, which will degrade the ISAR image quality for the traditional range-Doppler (RD) algorithm. In this paper, the received signal in a range bin is characterized as the multi-component polynomial phase signal (PPS) after the motion compensation, and a new approach of time-frequency representation, generalized polynomial Wigner-Ville distribution (GPWVD), is proposed for the azimuth focusing. The GPWVD is based on the exponential matched-phase (EMP) principle. Compared with the conventional polynomial Wigner-Ville distribution (PWVD), the EMP principle transfers the non-integer lag coefficients of the PWVD to the position of the exponential of the signal, and the interpolation can be avoided completely. For the GPWVD, the cross-terms between multi-component signals can be reduced by decomposing the GPWVD into the convolution of Wigner-Ville distribution (WVD) and the spectrum of phase adjust functions. The GPWVD is used in the ISAR imaging of ship targets, and the high quality instantaneous ISAR images can be obtained. Simulation results and measurement data demonstrate the effectiveness of the proposed new method. 相似文献
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本文给出了一种计算高射武器系统对目标实施一次射击时的效-费比的方法。该方法既考虑了高射武器击毁目标所产生的直接效益,也考虑了高射武器在保卫地面目标方面所产生的间接效益,因而更充分地描述了高射武器在战争中的作用。 相似文献
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李腊元 《系统工程与电子技术》1993,(2)
本文主要对典型的计算机双环网络拓扑进行了研究。提出了双环网络的形式描述模型,给出了典型双环拓扑的模型表示,并对这类典型双环的网络直径、平均跳跃距离和吞吐量——延迟特性进行了研讨。 相似文献
11.
王应明 《系统工程与电子技术》1991,(9)
本文对传统的多维偏好线性规划分析方法——LINMAP法进行改进,提出一种新的多维偏好线性规划分析方法。该方法运用加性加权法建立线性规划模型,同时引入任意小正数δ,使得评价结果更加符合于决策人偏好集。 相似文献
12.
费景高 《系统工程与电子技术》1994,(7)
本文对数字仿真模型的频域误差分析的一些结果进行综述。着重讨论数字仿真模型的特征根误差,传递函数误差,仿真子模型之间数据传输的频域误差和误差的一些补偿方法。文中也提出了一些需要解决的问题。 相似文献
13.
郭卫国 《系统工程与电子技术》1991,(10)
本文解决了正态精度增长问题中精度一阶矩μ、二阶矩ν的计算问题,从而为计算当前产品的精度铺平了道路。文中给出的μ,ν的精确计算公式,计算简便,便于工程使用。 相似文献
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Parallel Digital Simulation for the Control Problem in Differential Algebraic System 总被引:2,自引:0,他引:2
《系统工程与电子技术(英文版)》1996,(4)
Parallel Digital Simulation for the Control Problem in Differential Algebraic SystemChenLirong&LiuDegui(BeijingInstituteofCom... 相似文献
15.
Han Guodong Wang Hui & Wu Jiangxing. National Digital Switching System Engineering & Technological Research Center Information Engineering Univ. Zhengzhou P. R. China . Managment Coll. Tianjin Univ. Tianjin P. R. China 《系统工程与电子技术(英文版)》2005,16(4)
1.INTRODUCTION TomeettheincreasinglydemandsforQoS(qualityof service)inresourceboundedcommunicationsystem withintegrated services[1],recentpublications[2]sug gesttodividethewholetrafficmixintotwoaggre gates,oneforreal timetraffic(oftencalledstream traffic)andtheotherfornon real timetraffic(often calledelastictraffic).Thisisthebasisofclassofser vice(CoS).Toscheduleand/ormanagethepacket streaminarelativelyindependentarea(anau tonomoussystem),theproperlypacketlabelingalgo rithmaccordingtothe… 相似文献
16.
Deepak KAPUR 《系统科学与复杂性》2006,19(3):307-330
A method using quantifier-elimination is proposed for automatically generating programinvariants/inductive assertions.Given a program,inductive assertions,hypothesized as parameterizedformulas in a theory,are associated with program locations.Parameters in inductive assertions arediscovered by generating constraints on parameters by ensuring that an inductive assertion is indeedpreserved by all execution paths leading to the associated location of the program.The method can beused to discover loop invariants-properties of variables that remain invariant at the entry of a loop.Theparameterized formula can be successively refined by considering execution paths one by one;heuristicscan be developed for determining the order in which the paths are considered.Initialization of programvariables as well as the precondition and postcondition,if available,can also be used to further refinethe hypothesized invariant.The method does not depend on the availability of the precondition andpostcondition of a program.Constraints on parameters generated in this way are solved for possiblevalues of parameters.If no solution is possible,this means that an invariant of the hypothesizedform is not likely to exist for the loop under the assumptions/approximations made to generate theassociated verification condition.Otherwise,if the parametric constraints are solvable,then undercertain conditions on methods for generating these constraints,the strongest possible invariant of thehypothesized form can be generated from most general solutions of the parametric constraints.Theapproach is illustrated using the logical languages of conjunction of polynomial equations as well asPresburger arithmetic for expressing assertions. 相似文献
17.
数据包络分析(DataEnvelopementAnalysis)作为评价生产相对有效性的一种非参数方法,仅能评价生产的技术有效性,而在以市场为导向的生产经营和管理过程中,经营者和管理者不仅关心生产的技术有效性,而且,更关心生产的成本、收入和利润的有效性。因此,本文从公理化角度出发,系统地讨论在各种生产可能集情况下,评价生产成本、收入和利润有效性的ADEA模型以及评价生产配置有效性的理论和方法。 相似文献
18.
1.INTRODUCTION2-statesystemreliabilityoftenassumesthatthesystemisrepresentedbyaprobabilisticgraphG=(V,E),withasetV~{yi,v2,'',}ofvenicesandasetE~{el,e2,'',}ofedges(orlinks,branches)containedinit.Thesystemisfunctioningifthereexistsapathfromtheinputnodetotheoutputnode.Thusthereliabilityisconsideredwithamatterofconnectivityonlyandthereliabilityanalysishasbeenprimarilyconcernedwiththeenumerationofpathesorcutsinthereferences[1-4].Butinmanyphysicalsystemsuchaspowertransmissionsystems,oilorwat… 相似文献
19.
1. INTRODUCTIONClustering analysis is one of the major techniques in knowledge discovery in database (KDD),and other fields such as pattern recognition [1, 91. It is an approach to divide a data set illtosome categorically homogenous subsets called "clusters". The K-means algorithm [1] is a wellknown algorithm for this problem. It is a typical iterative hill-climbing algorithm, and thesolution obtained depends on the initial clustering. Although the K-means algorithm has beenapplied to … 相似文献
20.
杜芳 《系统工程与电子技术》1998,(3)
本文将前向网络的输入误差看作服从加性和乘性随机噪声,进行了网络输出误差的统计分析,并依此定义网络的灵敏度。在此基础上,分析了Sigmoid函数的斜度对网络灵敏度的影响,结合仿真实验,提出了一个降低前向网络灵敏度的有效方法。 相似文献